In environmental ethics, the precautionary principle states that parties should refrain from actions in the face of scientific uncertainties about serious or irreversible harm to public health or the environment. A similar principle is lacking when judging effects of information technology. Such a principle would be helpful in guiding discussions, and that is why we try to develop a precautionary principle for information technology in this paper.\ud
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As the effects of information technology are primarily social, social sustainability would be a key concept in developing the principle, where environmental sustainability fulfils this role in the traditional one. However, present definitions of social sustainability often consider it as an additional condition for environmental sustainability, rather than as an end in itself. Social sustainability, as meant in this paper, is the property of a development that it safeguards the continuity and stability of a social system. This may include maintaining trust and power relations in society. Based on this definition of social sustainability, we establish a precautionary principle with respect to the social sustainability of information technology.\ud
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The principle of informational precaution, as we call it, aims at protecting the social environment of technology by providing information security, just as the traditional precautionary principle aims at protecting the natural environment of technology by providing physical, chemical and biological safety. By providing causal insulation in the infosphere, i.e. separation of pieces of information, information technology may be able to protect the social environment. The principle of informational precaution then states that people should refrain from changing causal insulations in the infosphere, if there is uncertainty about possible serious or irreversible harm to society.\u
